feat: 添加角色选择系统及相关功能

新增角色卡片组件和角色选择逻辑
实现角色卡片动画效果和交互功能
添加初始角色数据配置
修改启动面板以支持角色选择
更新主题样式和UI布局

components/CharacterCards/MuyangDog.tscn

@@ -0,0 +1,27 @@
+[gd_scene format=3 uid="uid://bglwhggnbxxax"]
+
+[ext_resource type="PackedScene" uid="uid://m8a4nay1pmmg" path="res://components/Abstracts/CharacterCardBase.tscn" id="1_wq25g"]
+
+[sub_resource type="StyleBoxFlat" id="StyleBoxFlat_wq25g"]
+content_margin_left = 20.0
+content_margin_top = 20.0
+content_margin_right = 20.0
+content_margin_bottom = 20.0
+bg_color = Color(0, 0, 0, 0.70000005)
+border_blend = true
+corner_radius_top_left = 15
+corner_radius_bottom_right = 15
+corner_detail = 1
+
+[node name="MuyangDog" unique_id=1046363300 instance=ExtResource("1_wq25g")]
+theme_override_styles/panel = SubResource("StyleBoxFlat_wq25g")
+displayName = "牧羊犬"
+description = "恪守守护之责，性情沉稳忠诚。常年驻守边境旷野，坚守一方安宁，甘愿以身挡险，永远守护同伴与故土，恪守使命不离不弃。"
+fields = Array[int]([0, 8, 3])
+fieldValues = Array[float]([50.0, 0.15, -0.2])
+
+[node name="nameLabel" parent="wrapper/infoContainer" parent_id_path=PackedInt32Array(143242635) index="0" unique_id=516147781]
+text = "牧羊犬"
+
+[node name="descriptionLabel" parent="wrapper/infoContainer" parent_id_path=PackedInt32Array(143242635) index="1" unique_id=808054282]
+text = "恪守守护之责，性情沉稳忠诚。常年驻守边境旷野，坚守一方安宁，甘愿以身挡险，永远守护同伴与故土，恪守使命不离不弃。"